MERCEDES-BENZ GLS-Class SUV 2017 X166 Service Manual

Overhead control panel
FunctionPage
:pSwitches the left-hand
reading lamp on/off116
;c Switches the front inte-
rior lighting on116
=u Switches the rear inte-
rior lighting on or off116
?| Switches the front inte-
rior lighting/automatic inte-
rior lighting control off
117
Ap Switches the right-
hand reading lamp on/off116
B3 Opens/closes the pan-
orama roof with power tilt/
sliding panel and roller sun-
blinds
91
FunctionPage
CEyeglasses compartment296
DF Roadside Assistance
call button (mbrace system)310
EG SOS button (mbrace
system)309
Fï MB Info call button
(mbrace system)311
GRear-view mirror107
HButtons for the garage door
opener317
IMicrophone for mbrace
(emergency call system),
telephone and LINGUA-
TRONIC
1
1LINGUATRONIC is only available in combination with COMAND. Please observe the separate operating
instructions.
Overhead control panel39
At a glance

Door controlpanel
FunctionPage
:Opens th edoo r80
;%&Unlocks/locks
the vehicle80
=r 45=
Stores settings for the seat,
exterior mirrors and steering
column (memory function)
110
?Adjusts the seats94
A7Zö\
Adjusts and folds the exterior
mirrors in/out electrically
107
FunctionPage
BW Opens/closes the side
windows86
C± Opens/closes the
hinged power side windows86
Dp Opens/closes the tail-
gate84
En Activates/deactivates
the override feature for the
side windows in the rear
compartment
62
40Door control panel
At a glance

Panic alarm
XTo activate:press!button :for at least
one second.
A visual and audible alarm is triggered if the
alarm system is armed.
XTo deactivate: press!button :again.
or
XInsert the SmartKey into the ignition lock.
or
XPress the KEYLESS-GO Start/Stop button.
The KEYLESS-GO key must be in the vehicle.
Occupant safety
Introduction to the restraint system
The restraint system can reduce the risk of vehi- cle occupants coming into contact with parts of
the vehicle's interior in the event of an accident.
The restraint system can also reduce the forces to which vehicle occupants are subjected during
an accident.
The restraint system comprises:
Rseat belt system
Rair bags
Rchild restraint system
Rchild seat securing systems
The components of the restraint system work in
conjunction with each other. They can only
deploy their protective function if, at all times, all vehicle occupants:
Rhave fastened their seat belts correctly
(Ypage 44)
Rhave adjusted their seat and head restraint
properly (Ypage 94). As the driver, you also have to make sure that
the steering wheel is adjusted correctly.
Observe the information relating to the correct
driver's seat position (
Ypage 94).
You also have to make sure that an air bag can
inflate properly if deployed (
Ypage 46).
An air bag supplements a correctly worn seat
belt. As an additional safety device, the air bag
increases the level of protection for vehicle
occupants in the event of an accident. For exam-
ple, if, in the event of an accident, the protection
offered by the seat belt is sufficient, the air bags are not deployed. When an accident occurs, only
the air bags that increase protection in that par-ticular accident situation are deployed. How-
ever, seat belts and air bags generally do not
protect against objects penetrating the vehicle
from the outside.
Information on restraint system operation can
be found under "Triggering of the Emergency
Tensioning Devices and air bags" (
Ypage 53).
For information on children traveling with you in
the vehicle and on child restraint systems, see
"Children in the vehicle" (
Ypage 57).
Important safety notes
GWARNING
Modifications to the restraint system may
cause it to no longer work as intended. The
restraint system may then not perform its
intended protective function and may fail in an
accident or trigger unexpectedly, for example.
This poses an increased risk of injury or even fatal injury.
Never modify parts of the restraint system.
Never tamper with the wiring, the electronic
components or their software.
If it is necessary to modify components of the
restraint system to accommodate a person
with disabilities, contact an authorized
Mercedes-Benz Center for details. USA only:
for further information contact our Customer
Assistance Center at 1-800-FOR-MERCedes
(1‑800‑367‑6372).
Mercedes-Benz recommends that you only use
driving aids which have been approved specifi-
cally for your vehicle by Mercedes-Benz.
Occupant safety41
Safety
Z

Restraint system warning lamp
The functions of the restraint system are
checked after the ignition is switched on and at
regular intervals while the engine is running.
Therefore, malfunctions can be detected in
good time.
The6 restraint system warning lamp in the
instrument cluster lights up when the ignition is
switched on. It goes out no later than a few sec-
onds after the vehicle is started. The compo-
nents of the restraint system are in operational
readiness.
A malfunction has occurred if the 6restraint
system warning lamp:
Rdoes not light up after the ignition is switched
on
Rdoes not go out after a few seconds with the
engine running
Rlights up again while the engine is running
GWARNING
If the restraint system is malfunctioning,
restraint system components may be trig-
gered unintentionally or may not deploy as
intended during an accident. This can affect
for example the Emergency Tensioning
Device or the air bag. This poses an increased
risk of injury or even fatal injury.
Have the restraint system checked and
repaired in a qualified specialist workshop as
soon as possible.
PASSENGER AIR BAG indicator lamp
PASSENGER AIR BAG ON indicator lamp :and
PASSENGER AIR BAG OFF indicator lamp ;are
part of the Occupant Classification System
(OCS). The indicator lamps display the status of the
front-passenger front air bag.
RPASSENGER AIR BAG ON lights up for 60 sec-
onds, subsequently both indicator lamps are
off (PASSENGER AIR BAG ON and OFF): the
front-passenger front air bag is able to deploy
in the event of an accident.
RPASSENGER AIR BAG OFF lights up: the front-
passenger front air bag is deactivated. It will
then not be deployed in the event of an acci-
dent.
If the PASSENGER AIR BAG ON indicator lamp is
off, only the PASSENGER AIR BAG OFF indicator lamp shows the status of the front-passenger
front air bag. The PASSENGER AIR BAG OFF
indicator lamp may be lit continuously or be off.
Depending on the person in the front-passenger
seat, the front-passenger front air bag must
either be deactivated or enabled; see the fol-
lowing points. You must make sure of this both
before and during a journey.
RChildren in a child restraint system:
whether the front-passenger front air bag is
enabled or deactivated depends on the instal-led child restraint system, and the age and
size of the child. Therefore, be sure to observe
the notes on the "Occupant Classification
System (OCS)" (
Ypage 48) and on "Chil-
dren in the vehicle" (Ypage 57). There you
will also find instructions on rearward and
forward-facing child restraint systems on the
front-passenger seat.
RAll other persons: depending on the classi-
fication of the person in the front-passenger
seat, the front-passenger front air bag is ena-
bled or deactivated (
Ypage 48). Be sure to
observe the notes on "Seat
belts“ (
Ypage 42) and "Air bags"
(Ypage 46). There you can also find infor-
mation on the correct seat position.
Seat belts
Introduction
Seat belts are the most effective means of
restricting the movement of vehicle occupants
in the event of an accident or the vehicle rolling over. This reduces the risk of vehicle occupants
coming into contact with parts of the vehicle
interior or being ejected from the vehicle. Fur-
thermore, the seat belt helps to keep the vehicle
42Occupant safety
Safety

occupant in the best position in relation to the
air bag.
The seat belt system comprises:
RSeat belts
REmergency Tensioning Devices for the front
seat belts and the outer seat belts in the sec-
ond row of seats as well as the seat belts in
the third row
RSeat belt force limiters for the front seat belts
and the outer seat belts in the second row of
seats as well as the seat belts in the third row
If the seat belt is pulled out of the belt outlet
quickly or with a jerky movement, the belt
retractor locks. The belt strap cannot be extrac-
ted any further.
The Emergency Tensioning Device tightens the
seat belt in an accident, pulling the belt close
against the body. However it does not pull the
vehicle occupant back in the direction of the
backrest.
The Emergency Tensioning Device does not cor- rect an incorrect seat position or the routing of
an incorrectly fastened seat belt.
When triggered, a seat belt force limiter helps to
reduce the force exerted by the seat belt on the
vehicle occupant.
The seat belt force limiters for the front seats are
synchronized with the front air bags, which
absorb part of the deceleration force. This can
reduce the force exerted on the vehicle occu-
pants during an accident.
!If the front-passenger seat is unoccupied,
do not insert the belt tongue into the buckle of the front-passenger seat. This may otherwise
lead to the triggering of the Emergency Ten-
sioning Device in the event of an accident,
which will then need to be replaced.
Important safety notes
The use of seat belts and child restraint systemsis required by law in:
Rall 50 states
Rthe U.S. territories
Rthe District of Columbia
Rall Canadian provinces
Even where this is not required by law, all vehicle
occupants should correctly fasten their seat
belts before starting the journey.
GWARNING
If the seat belt is not worn correctly, it cannot
perform its intended protective function. An
incorrectly fastened seat belt can also cause
injuries, for example, in the event of an acci-
dent or when braking or changing direction
abruptly. This poses an increased risk of injury
or even fatal injury.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sit-
ting properly.
GWARNING
The seat belt does not offer the intended level of protection if you have not moved the back-
rest to an almost vertical position. When brak-
ing or in the event of an accident, you could
slide underneath the seat belt and sustain
abdomen or neck injuries, for example. This
poses an increased risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always ensure that the backrest
is in an almost vertical position and that the
shoulder section of your seat belt is routed
across the center of your shoulder.
GWARNING
Persons less than 5 ft (1.50 m) tall cannot
wear the seat belt correctly without an addi-
tional and suitable restraint system. If the
seat belt is not worn correctly, it cannot per-
form its intended protective function. An
incorrectly fastened seat belt can also cause
injuries, for example, in the event of an acci-
dent or when braking or changing direction
abruptly. This poses an increased risk of injury or even fatal injury.
For this reason, always secure persons under
5 ft (1.50 m) tall in suitable additional restraint
systems.
If a child younger than twelve years old and
under 5 ft (1.50 m) in height is traveling in the
vehicle:
Ralways secure the child in a child restraint
system suitable for this Mercedes-Benz vehi-
Occupant safety43
Safety
Z

cle. The child restraint system must be appro-
priate to the age, weight and size of the child
Ralways observe the instructions and safety
notes on "Children in the vehicle"
(
Ypage 57) in addition to the child restraint
system manufacturer's installation and oper-
ating instructions
Rbe sure to observe the instructions and safety
notes on the "Occupant classification system
(OCS)" (
Ypage 48)
GWARNING
The seat belts may not perform their intended protective function if:
Rthey are damaged, modified, extremely
dirty, bleached or dyed
Rthe seat belt buckle is damaged or
extremely dirty
Rthe Emergency Tensioning Devices, belt
anchorages or inertia reels have been modi-
fied.
Seat belts may be damaged in an accident,
although the damage may not be visible, e.g.
due to splinters of glass. Modified or damaged
seat belts may tear or fail, e.g. in an accident.
Modified Emergency Tensioning Devices
could accidentally trigger or fail to deploy
when necessary. This poses an increased risk
of injury or even fatal injury.
Never modify the seat belts, Emergency Ten-
sioning Devices, belt anchorages and inertia
reels. Make sure that the seat belts are
undamaged, not worn out and clean. Follow-
ing an accident, have the seat belts checked
immediately at a qualified specialist work-
shop.
Only use seat belts that have been approved for
your vehicle by Mercedes-Benz.
Proper use of the seat belts
Observe the safety notes on the seat belt
(Ypage 43).
All vehicle occupants must be wearing the seat
belt correctly before beginning the journey. Also
make sure that all vehicle occupants are always
wearing the seat belt correctly while the vehicle
is in motion. When fastening the seat belt, always make sure
that:
Rthe seat belt tongue is only inserted to the belt
buckle belonging to that seat.
Rthe seat belt is tight across your body.
Avoid wearing bulky clothing, e.g. a winter
coat.
Rthe seat belt is not twisted.
Only then can the forces which occur be dis-
tributed over the area of the belt.
Rthe shoulder section of the belt is always
routed across the center of your shoulder.
The shoulder section of the belt must not
come into contact with your neck or be routed
under your arm. Where possible, adjust the
seat belt to the appropriate height.
Rthe lap belt passes tightly and as low down as
possible across your lap.
The lap belt must always be routed across
your hip joints and not across your abdomen.
This applies particularly to pregnant women.
If necessary, push the lap belt down to your
hip joint and pull it tight using the shoulder
section of the belt.
Rthe seat belt is not routed across sharp, poin-
ted or fragile objects.
If you have su
ch i
tems located on or in your
clothing, e.g. pens, keys or eyeglasses, store
these in a suitable place.
Ronly one person is using a seat belt at a time.
Infants and children must never travel sitting
on the lap of a vehicle occupant. In the event of an accident, they could be crushed
between the vehicle occupant and seat belt.
Robjects are never secured with a seat belt if
the seat belt is also being used by one of the
vehicle's occupants.
Also ensure that there are never objects
between a person and the seat, e.g. cushions.
Seat belts are only intended to secure and
restrain vehicle occupants. Always observe the
"Loading guidelines" for securing objects, lug-
gage or loads (
Ypage 294).
Fastening and adjusting the seat belts
Observe the safety notes on the seat belt
(Ypage 43) and the notes on correct use of seat
belts (Ypage 44).
44Occupant safety
Safety

Basic illustration
XAdjust the seat (Ypage 94).
The seat backrest must be in an almost ver-
tical position.
XPull the seat belt smoothly from the belt outlet
and engage belt tongue ;into belt
buckle :.
The seat belt on the driver’s seat and the
front-passenger seat may be tightened auto-
matically, see "Belt adjustment"
(
Ypage 45).
XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
The shoulder section of the seat belt must
always be routed across the center of the shoul-
der. Adjust the belt outlet if necessary.
XTo raise: slide the belt outlet upwards.
The belt outlet will engage in various posi-
tions.
XTo lower: hold belt outlet release =and slide
belt outlet downwards.
XLet go of belt outlet release =in the desired
position and make sure that the belt outlet
engages.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. Further information can be found under
"Special seat belt retractor" (
Ypage 57).
Releasing seat belts
!Make sure that the seat belt is fully rolled up.
Otherwise, the seat belt or belt tongue will be
trapped in the door or in the seat mechanism.
This could damage the door, the door trim
panel and the seat belt. Damaged seat belts
can no longer fulfill their protective function and must be replaced. Visit a qualified spe-
cialist workshop.
XPress the release button in the belt buckle,
hold the belt tongue firmly and guide the belt
back.
Seat belt adjustment
The seat-belt adjustment is an integral part of
the PRE-SAFE®convenience function. This func-
tion adjusts the driver's and front-passenger
seat belt to the upper body of the occupants.
The belt strap is tightened slightly when:
Rthe belt tongue is engaged in the buckle and
Rthe ignition is switched on
The seat-belt adjustment will apply a certain
retraction force if any slack is detected between
the vehicle occupant and the seat belt. Do not
hold on to the seat belt tightly while it is adjust-
ing.
You can switch the seat-belt adjustment on and
off in the on-board computer (
Ypage 240).
Belt warning for the driver and front
passenger
The 7 seat belt warning lamp in the instru-
ment cluster is a reminder that all vehicle occu-
pants must wear their seat belts. It may light up
continuously or flash. In addition, there may be
a warning tone.
Regardless of whether the driver's seat belt has
already been fastened, the 7seat belt warn-
ing lamp lights up for six seconds each time the engine is started. If, after six seconds, the driver
or front-passenger seat belt has not been fas-
tened and the doors are closed, the 7seat
belt warning lamp lights up. As soon as the driv-
er's and front-passenger seat belts are fastened
or a front door is opened again, the 7seat
belt warning lamp goes out.
If the driver's seat belt is not fastened after the
engine is started, an additional warning tone will
sound. The warning tone switches off after six
seconds or once the driver's seat belt is fas-
tened.
If the vehicle's speed exceeds 15 mph
(25 km/h) once and the driver's and front-
passenger seat belts are not fastened, a warning
tone sounds. A warning tone also sounds with
increasing intensity for 60 seconds or until the
Occupant safety45
Safety
Z

driver or front passenger have fastened their
seat belts.
If the driver or front passenger unfasten their
seat belts during the journey, the seat belt warn-
ing is activated again.
Air bags
Introduction
The installation point of an air bag can be rec-
ognized by the AIR BAG symbol.
An air bag complements the correctly fastened
seat belt. It is no substitute for the seat belt. The
air bag provides additional protection in appli-
cable accident situations.
Not all air bags are deployed in an accident. The
different air bag systems function independ-
ently from one another (
Ypage 53).
However, no system available today can com-
pletely eliminate injuries and fatalities.
It is also not possible to rule out a risk of injury
caused by an air bag due to the high speed at
which the air bag must be deployed.
Important safety notes
GWARNING
If you do not sit in the correct seat position,
the air bag cannot protect as intended and
could even cause additional injury when
deployed. This poses an increased risk of
injury or even fatal injury.
To avoid hazardous situations, always make
sure that all of the vehicle's occupants:
Rhave fastened their seat belts correctly,
including pregnant women
Rare sitting correctly and maintain the great-
est possible distance to the air bags
Rfollow the following instructions
Always make sure that there are no objects
between the air bag and the vehicle's occu-
pants.
RAdjust the seats properly before beginning
your journey. Always make sure that the seat
is in an almost upright position. The center of the head restraint must support the head at
about eye level.
RMove the driver's and front-passenger seats
as far back as possible. The driver's seat posi-
tion must allow the vehicle to be driven safely.
ROnly hold the steering wheel on the outside.
This allows the air bag to be fully deployed.
RAlways lean against the backrest while driv-
ing. Do not lean forwards or lean against the
door or side window. You may otherwise be in
the deployment area of the air bags.
RAlways keep your feet in the footwell in front
of the seat. Do not put your feet on the dash-
board, for example. Your feet may otherwise
be in the deployment area of the air bag.
RFor this reason, always secure persons less
than 5 ft (1.50 m) tall in suitable restraint sys-
tems. Up to this height, the seat belt cannot
be worn correctly.
If a child is traveling in your vehicle, also
observe the following notes:
RAlways secure children under twelve years of
age and less than 5 ft (1.50 m)tall in suitable
child restraint systems.
RChild restraint systems should be installed on
the rear seats.
ROnly secure a child in a rearward-facing child
restraint system on the front-passenger seat
when the front-passenger front air bag is
deactivated. If the PASSENGER AIR BAG OFF
indicator lamp is permanently lit, the front-
passenger front air bag is deactivated
(
Ypage 42).
RAlways observe the instructions and safety
notes on the "Occupant Classification System
(OCS)" (
Ypage 48) and on "Children in the
vehicle" (Ypage 57 )in addition to the child
restraint system manufacturer's installation
and operating instructions.
Objects in the vehicle interior may prevent
an air bag from functioning correctly. Before
starting your journey and to avoid risks resulting from the speed of the air bag as it deploys, make
sure that:
Rthere are no people, animals or objects
between the vehicle occupants and an air
bag.
Rthere are no objects between the seat, door
and B-pillar.
Rno hard objects, e.g. coat hangers, hang on
the grab handles or coat hooks.
46Occupant safety
Safety

Rno accessories, such as cup holders, are
attached to the vehicle within the deployment
area of an air bag, e.g. to doors, side windows,
rear side trim or side walls.
Rno heavy, sharp-edged or fragile objects are in
the pockets of your clothing. Store such
objects in a suitable place.
GWARNING
If you modify the air bag cover or affix objects
such as stickers to it, the air bag can no longer
function correctly. There is an increased risk
of injury.
Never modify an air bag cover or affix objects
to it.
GWARNING
Sensors to control the air bags are located in
the doors. Modifications or work not per-
formed correctly to the doors or door panel-
ing, as well as damaged doors, can lead to the
function of the sensors being impaired. The air
bags might therefore not function properly
anymore. Consequently, the air bags cannot
protect vehicle occupants as they are
designed to do. There is an increased risk of
injury.
Never modify the doors or parts of the doors.
Always have work on the doors or door pan-
eling carried out at a qualified specialist work-
shop.
Front air bags
!Do not place heavy objects on the front-
passenger seat. This could cause the system
to identify the seat as being occupied. In the
event of an accident, the restraint systems on
the front-passenger side may be triggered
and have to be replaced.
Driver's air bag :deploys in front of the steer-
ing wheel. Front-passenger front air bag ;
deploys in front of and above the glove box.
When deployed, the front air bags offer addi-
tional head and thorax protection for the occu-
pants in the front seats.
The PASSENGER AIR BAG OFF indicator lamp
informs you about the status of the front-
passenger front air bag (
Ypage 42).
The front-passenger front air bag will only
deploy if:
Rthe system, based on the OCS weight sensor
readings, detects that the front-passenger
seat is occupied (
Ypage 48). The
PASSENGER AIR BAG OFF indicator lamp is
not lit (
Ypage 49)
Rthe restraint system control unit predicts a
high accident severity
Driver's knee bag
Driver's knee bag :deploys under the steering
column. The driver's knee bag is triggered
together with the front air bag.
The driver's knee bag offers additional thigh,
knee and lower leg protection for the occupant
in the driver's seat.
Occupant safety47
Safety
Z

Side impact air bags
GWARNING
Unsuitable seat covers can obstruct or pre-
vent deployment of the air bags integrated
into the seats. Consequently, the air bags
cannot protect vehicle occupants as they are designed to do. In addition, the operation of
the occupant classification system (OCS)
could be adversely affected. This poses an
increased risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
Front side impact air bags :and second row
rear side impact air bags ;deploy next to the
outer bolster of the seat backrest.
When deployed, the side impact air bag offers
additional thorax protection. It also offers addi-
tional pelvis protection for occupants in the
front seats. However, it does not protect the:
Rhead
Rneck
Rarms
In the event of a side impact, the side impact air
bag is deployed on the side on which the impact
occurs.
The side impact air bag on the front-passenger
side deploys under the following conditions:
Rthe OCS system detects that the front-
passenger seat is occupied or
Rthe belt tongue is engaged in the belt buckle
of the front-passenger seat
If the belt tongue is engaged in the belt buckle,
the side impact air bag on the front-passenger
side deploys if an appropriate accident situation
occurs. In this case, deployment is independent of whether the front-passenger seat is occupied
or not.
Window curtain air bags
Window curtain air bags :are integrated into
the side of the roof frame and deploy in the area
extending from the front door (A-pillar) to the
rear side window (D-pillar).
When deployed, the window curtain air bag
enhances the level of protection for the head.
However, it does not protect the chest or arms.
In the event of a side impact, the window curtain
air bag is deployed on the side on which the
impact occurs.
If the system determines that they can offer
additional protection to that provided by the
seat belt, a window curtain air bag may be
deployed in other accident situations
(
Ypage 53).
Occupant Classification System
(OCS)
Introduction
The Occupant Classification System (OCS) cat-
egorizes the person in the front-passenger seat.
Depending on that result, the front-passenger
front air bag is either enabled or deactivated.
The system does not deactivate:
Rthe side impact air bag
Rthe window curtain air bag
Rthe Emergency Tensioning Devices
48Occupant safety
Safety